CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ 31.9	$ 136.3	$ (32.7)	$ 261.5
Other comprehensive earnings (loss), net of tax
Foreign currency translation adjustments, net of tax	49.0	(2.7)	20.9	(26.9)
Unrealized gain on hedging instruments	6.4	7.6	11.7	16.4
Unrealized gain on benefit plans	4.1	2.1	8.4	4.3
Total other comprehensive earnings (loss), net of tax	59.5	7.0	41.0	(6.2)
Comprehensive earnings	$ 91.4	$ 143.3	$ 8.3	$ 255.3